Electric switch.



J. L. McQUARRIE.

ELECTRIC SWITCH.

APPLICATION FILED nEc,2. 191s.

1,252,465. Patented Jan. 8,1918.

James A. /7- Quark/e.

UNITED STATES PATENT OFFICE.

JAMES L. MOQUARRIE, OF TCLAIR, NEW JERSEY, ASSIGNOR T0 WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

ELECTRIC SWITCH.

Specification of Letters Patent.

Patented Jan. 8, 1918.

Application filed December 2, 1916. Serial No. 134,602.

To all whom it may concern Be it known that I, J AMES L. MCQUARRIE, a citizen of the United States, residing at Montclair, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Electric Switches, of which the following is a full, clear, concise, and exact description.

This invention relates to electric switches, and particularly to the type of switches used in automatic and semi-automatic telephone systems.

The principal object of this invention is to provide a switch in which a contact is moved over a .terminal bank under the ef-' fect of gravity. Another object is: to effect not only the association of a movable contact with a desired terminal but also the restoration of this contact to. normal position by the utilization of the same mechanism.

In operation, a movable contact normally located at the top of the terminal bank is released in response to group selecting impulses and moves under the effect of gravity to the bottom of the selected group of terminals. Thereupon the contact is moved upwardly a step at a time to locate a terminal in a desired condition in said group. On location of such terminal, the contact is associated therewith, and succeeding apparatus is operated to eflect connection with the called party in any well-known manner. On completion of conversation, the contact is moved upwardly a step at a time to normal position, where it is held ready for subsequent use.

Referring now to the drawing which illustrates one embodiment of the invention, Figure 1 is a side elevation of the switch, together with a diagrammatic showing of the circuits utilized in its operation; Fig. 2

is a cross section on the line 2-2 of Fig. 1v

showing the arrangement of the movable contact set with respect to its terminal bank; and Fig. 3 is a cross section on the line 33 of Fig. 1 showing the commutator and the movable brushes in cotiperation therewith.

The switch proper comprises two parallel plates 10, spaced slightly apart and secured to any suitable base by brackets 11 and 12. The lower bracket 12 serves to carry a commutator 13. Between the plates 10 there is slidably mounted a toothed elevator rod 14 carrying a bracket 15 on its lower end.

A brush set 16 is secured to the bracket 15 and comprises brushes 17, 18, 19, 20, 21, 22, 23 and 24, movable over commutator strips 17, 18, 19, 20, '21, 22, 23 and 24' of the commutator plate 13. The commutator 13 is provided with three strips upon one side, while five are shown upon the other. But one of the five is, however, for the purposes of the present invention. In Fig. 1 the two'sides of the commutator are shown as lying side by side in the same plane, whereas their true relation is shown in Fig. 3. The upper end of the bar 14 carries a movable contact set 25 having contacts 26, 27 and 28 arranged for engagement with sets'of terminal strips 26, 27' and 28, respectively, of the terminal bank 29. To guide the movement of the elevator bar, brackets 30 and 31 are secured to the frame and carry between them a rod 32, overwhich rod slides a guide arm 33 secured to the bar 14. An idler wheel 34 mounted between the parallel plates 10 facilitates movement of the bar 14. The space plates 10 each have extensions 35, 36 and 37 thereon. The extensions 36 have secured to them a pair of electromagnets 38 and 39. The magnet 38 is a group selecting magnet and extends above the extensions 36 and has its armature 40 pivotally mounted between the extensions 35, while the magnet 39, which operates as a stepping magnet, extends below the extensions 36 and as its armature 41 pivot ally mounted between the extensions 37. 1

armature 40 away from its magnet 38, while an adjusting screw 44, mounted in a bridging piece 45 extending between the. extensions 35, facilitates proper adjustment of the armature. The armature 41 of magnet 39 has a pawl 46 pivoted thereto. This pawl 46 carries a lug 47 which normally engages a stop pin 48 carried on one of the plates 10 and which serves to disengage the pawl 46 from the teeth of the bar 14. Thespring 49, however, operates to force the pawl 46 into engagement with the teeth of the bar 14, and on attraction of the armature 41, the

pawl engages said bar 14 and carries it upwardly one tooth.

To escape the .bar 14 the proper number of teeth for each group it is necessary to' hold the pawl 42 out of engagement until the number of teeth corresponding to agroup have been passed. This is accomplished by keeping the magnet 38 energized a proper interval of'time. This is done by arranging the pawl 42 to escape at least one tooth on each attraction of the armature 40. The commutator 13 has a commutator strip 24 with which the brush 24 engages. This commutator strip is scent that the brush 24 rests on an insulated portion when the brush-set 26 is on the bottom terminal of each of the groups into which the terminals are divided. The conducting portions have a ground connection and are cut so that on each attraction of the armature 38 and withdrawal of the pawl 42, the bar 14 moves the brush 24 on to the conducting. portions of the strip 24 The brush 24 has a conductor 100'leading therefrom to the conductor 76, through a side-switch arm 99 closed in the first position. This arrangement results in the magnet 38 attracting its. armature 40 and disengagin the pawl 42 from the bar 14 on receipt o the first roup selecting impulse. The bar 14, in falllng, will bring the brush 24 into engagement with a conducting portion of the grounded stri 24' before the armature 40 can fall ofl'. E holding circuit is thus formed for the magnet 38, extending from grounded battery, conductor 77, magnet 38, conductor 76, side-switch arm 99 inits first position, conductor 100, brush 24, conducting portion of commutator strip 24 to ground. The magnet 38 remains energized'until an insulating portion of the strip 24' is reached, when the pawl 42 again engagesthe bar 14, stopping the brush set 25 at the bottom terminal of the first group. The sender used in sending the group impulses is so arranged as to time the impulses, so that the second impulse will be received just after the bar 14 has reached the bottom of the first group, when the magnet 38 would be again energized and the brush-set 25 moved to the bottom of the next oup, and so on until the bottom of the deslred group has been reached.

Downward movement of the elevator bar moves the contact set 25 over the bank 29 in grou steps until the bottom of the group selecte by the magnet 38'has been reached. Thereupon magnet 39 is energized and moves the bar 14 upwardly a ste at a time until th contact set 25 is locate on the terminals of the desired line. The magnet 39 is then deenergized and remains so until completion of the conversation, when it is again energized and moves the elevator rod upwardly step by step until. the normal position is reached. A contact 50 normally closed, but open on energization of the magnet 39,'is included in the operating circuit of this magnet to make the same self-interrupting.

Conductors 60 and 61 are associated with the substation set (not shown) of a calling subscriber, and when a call is initiated at the substation, a circuit is completed for the relay 62 over a circuit extending from ground, left-hand winding of relay 62, conductor 63, side-switch arm 64 in first position, conductor 61, subscribers set (not shown), conductor 60, side-switch arm 65 in first position, conductor 66, right-hand winding of relay 62 to grounded attery. Relay 62 on pulling up completes a circuit for a slow release relay 67, extending from ground, left-hand armature and back contact of relay 68, conductor 69, armature and front contact of relay 62, conductor 70, and why 67 to grounded battery. Relay 67 pulls up, preparing a circuit for a second slow release relay 71. Impulses are sent through the relay,62 in the manner usual in automatic telephony to select the desired group through operation of the group magnet 38. The armature of the relay 62, fall- .positionhconductor 7 6 magnet 38 and conductor to grounded battery. This makes the magnet 38 responsive to the group selecting impulses, and on each energization of magnet 38, the pawl 42 is held out while the contact set 25 is omitted to move over one group of terminals. Succeeding impulses repeat this operation until the contact set 25 is at the bottom of the desired group.

On energization of relay 71, a circuit is completed for side-switch escape relay 78, from ground, armature and front contact of relay 71, conductor 79, side-switch arm 80, first position, conductor 81 and relay 78 to grounded battery. Relay 71 being slow to release holds up until the rela 62 holds-up for a longer interval at the an .of the group impulses. This results in deenergizin relay 71, which in turn opens the circuit 0 relay would have their test terminals in the bank 1 29 ungrounded, while idle trunk terminals would have ground placed thereon. The relay 62 remains up at the end of the group impulses and a circuitis completed for the stepping magnet 39, this circuit extending 0 from ground, left-hand-armature and back contact of relay 68, conductor 69, armature and front contact of relay 62, conductors 7 0 and 82, armature and back contact of escape 5 relay 78, conductor 83, side-switch arm 4 in second position, conductor 85, contac 50,

conductor" 86, stepping magnet 39, conductor 87 to grounded battery, The magnet 39 being self-interrupting at ,the contact 50, steps the contact set 25 upwardly a step at a t1me until the test brush 26 contacts with a test terminal 26' of an idle trunk. On reaching such a terminal a circuit is completed from grounded terminal 2 6, its contact 26, conductor 88, brush 19, commutator 19', conductor 89, side switcharm 80, second position, conductor 81, and side-switch relay 78 tov grounded battery. Side-switch relay is,energized, and pulling up steps all the side-switch arms to the third position, opening the circuit of magnet 39 and leaving the contact set 35 onthe terminal of the desiredtrunk.

In the thirdposition of the side switch the conductors and 61 are extended over the conductors 90 and 91, commutator strips 17' and 18, brushes 17 and 18, conductors 92 and 93, contacts 28 and 27, and terminals 28 and 27 respectively to succeeding apparatus which would be operated by other series of impulses to secure connection with the desired'subscriber. Ground is taken off of the test terminal 26' for the movablecontact set 25 by the operation of the succeeding apparatus, and remains off until completion of conversation, when the action of the succeeding apparatus again places ground u'pbn this test terminal 26. A circuitis thereupon completed for the side-switch escape relay 78 over a circuit the same as previously traced except that the side-switch arm 80 is now in its .third position, in which, however, it still connects with the conductor 89. The relay 78 on pulling up immediately moves all the side-switch arms to fourth position, whereupon relay 68 is energized over a circuit extending from ground, switch. arm 94 in its fourth position, conductor 95, lefthand winding of relay 68 to grounded battery. Relay 68 thereupon pulls up and locks up in a c1rcuit extending from grounded battery, right-hand winding of relay 68, con

ductor 96, right-hand armature and front contact of relay 68, and off-normal contact 97 to ground. The left-hand armature closes a circuit for the stepping magnet 39, extending from ground, front contact and lefthand armature of relay 68, conductors 98 and 85, interrupting contact 50,"v conductor 86, magnet 39, conductor 87 to grounded battery. Stepping magnet. 39 thereupon moves the contact set 25 upwardly until it reaches normal position, in which the oilnormal contact 97 is opened, denergizing 5 the relay 68, and consequently opening the circuit of the stepping magnet 39. The pawl 42 holds the bar 14 in normal position. The elevating bar 14 is arranged to operate the side switch and restore all the sideswitch arms to first osition as soon as the ofl'normal contact 97 has been opened, but other means may be used to efiect this result. To accomplish restoration of the switch to normal, in event of the calling party hanging up before the desired trunk has been located, the apparatus is arranged to operate as follows: If the side-switch arms be in the first position when the calling party hangs up, the relay'62 would be deenergized and the relay 67 would fall ofi, opening the circuit to the side-switch relay 78. This relay would thereupon fall off and move all the side-switch arms to second position. In this position, the relays 62 and 67 being denergized, a circuit is completed for the relay 68 extending from grounded battery, left-hand winding of relay 68, conductor 95, side-switch arm 94in second posi-. tion, conductor 99, armature and back contact of relay 67, conductor 72, armature and back contact of relay 62, conductor 69, and left-hand armature and back contact of'relay 68 to ground. Relay 68 thereupon operates to restore the switch to normal, as

in the usual operation. of the system.

What is claimed is:

1. In an automatic switch, a plurality of stationary contacts arranged in groups, a carriage, a movable contact carried thereby electrically controlled means normally holding saidcarriage against movement, and means controlled by movement of said carriage to render said holding means inoperative while said movable contact passes over a group of stationary contacts.

2. In an automat1c switch, a,plurality of stationary contacts, a carriage, a movable contact carried thereby, a commutator, a brush arranged for engagement with said commutator and movable with said carriage,

means normally holding said carriage against movement, means to operate said holding means to permit movement of said carriage and means controlled by movement of said brush over said commutator to release ;said holding means at certain positions of said carriage only.

3. In an automatic'swltch, a plurality of stationary contacts arranged in groups, a carriage, a movable contact carried thereby, means normally holding said carriage agalnst' movement, means ,to operate said hold ng means to permit movement of said carnage, and means controlled by the movementof said carriage to cause said movable contact to be advanced in group steps.

' 4. In an automatic switch, a plurality of stationary contacts arranged ingroups, a

carriage, a movable contact carried thereby, means normally holding said carriage against movement, means to operate saidholding means to permit movement of said carriage, and means controlled by movement of said contact to render inoperative v carriage, a movable contactcarried thereby,

means normally holding said carriage against movement, means to operate said holding means to permit movement of said carriage, means controlled by movementof said carriage to position'said movable contact at a group extremity, and means to associate said movable contact with a desired stationary contact-in such group.

6.'In an automatic switch, a plurality of stationary contacts arranged in groups, a carriage, a movable contact carried thereby, means normally holding said carriage against movement, means to operate said holding means to permit movement of said carriage, means controlled by movement of said carriage .to move said contact in group steps, and means to move said carriage to associate said movable contact with a desired stationary contact in a desired group.

7. In an automatic switch, a plurality of stationary contacts arranged in groups, a carriage, a movable contact carried thereby, means normally holding said carriage against movement, means to operate said holding means to permit movement of said carriage, means controlled by movement of said carriage to advance said movable contact in group steps to one end of a desired group, and a single means to move said movable contact into association with a desired stationary contact inthe desired group and to return sald carriage to its normal posi tion.

8. In an automatic switch,-a panel contact bank, a vertically movable carriage, a contact carried thereby, means normally holding,

said carriage against downward movement, means to release said holding means to permit movement of said carriage under the intheme of gravity, and means contrplled by movement of said carriage to make said holding means eflective at certain positions of said carriage.

9. In an automatic switch, a panel contact bank, a plurality of stationary contacts arranged in groups therein, a vertically movable carriage, a movable contact carried thereby, means normally holding said carriage against downward movement, means to operate said holding means to permit movement of said carriage under the infiu ence of gravity, and means controlled by movement of said carriage to render said holding means inoperative while said movable contact passes over a group of stationary contacts.

10. In an automatic switch,a panel contact bank, a plurality of stationary contacts arranged in groups therein, a vertically movable carriage, a movable contact carried thereby, means normally holding said carriage against downward movement, means to operate said holding means to permit movement of said carriage under the influence of gravity, means controlled by movement of said carriage to position said movable con-.

tact at the bottom of a desired group of stationary contacts, and a single means to advance said carriage upwardly to move said movable contact into engagement with a desired stationary contact and to return said carriage to normal position.

In witness whereof, I hereunto subscribe my name this 29th day of November, A. D. 19:16.

James L. trcouaianm. 

